The goals of these studies have been to establish and characterize malignant T cell lines, to optimize the methods for serum free growth of normal and malignant T cell lines, to define growth factors and growth factor receptors for these lines, to examine other lymphokines produced by these lines and to determine the effects of monoclonal antibodies, monoclonal antibody conjugates, biological and chemotherapeutic agents on these lines. We have established a new HTLV(+) permanent T Cell line, Hut 516, which has been in permanent culture for greater than 2 years. The line produces a number of lymphokines listed below. We have defined a serum free BITES medium which supports the growth of this and other T cell lines as well as serum supplemented medium. We have characterized a new monoclonal antibody, anti-HV, which binds to the TCGF receptor. However, the epitope of the receptor to which it binds does not block binding of TCGF or anti-tac. The antibody may be useful in the diagnosis and treatment of HTLV associated adult T cell lymphomas (ATL). It may also be useful in studies of the TCGF receptor especially after treatment with anti-Tac. In concert with our clinical serotherapy trials we have established methods for evaluating the immunoreactivity of monoclonal antibodies conjugated with drugs, toxins or radionuclides. We have shown that 125I conjugated antibodies (T101, 9.2.27) are capable of selective cell killing (up to 3 logs) of malignant cells in vitro. We have developed an in vitro model for these studies.